Accordion shift mechanism



Dec. 23, 1947. A. J..WA LT 2,433,310

I ACCORDION SHIFT MECHANISM Filed Feb. 28, 1946 2 Sheets-Sheet 1 Fl[i.- l

Dec. 23, 1947 T 2,433,310

ACCORDION SHiFT MECHANISM 2 Sheets-Sheet 2 Filed Feb. 28, 1946 IZZ I32 I30 #6 flTTjK/Yflfi Patented Dec. 23, 1947 ACCORDION SHIFT MECHANISM Albert J. Walt,

Rudolph Wurlitzer corporation De Kalb, Ill., assignor to The Company, Chicago, 111., 2.

Application February 28, 1946, Serial No. 650,822 7 Claims. (01. 84-376) This invention relates to a shift mechanism and the supporting valve plate therefor operable by a conveniently located shift key or bar to shift the slide valves controlling the treble or bass reed blocks respectively.

The invention is particularly directed to the positive and simplified actuating mechanism operable each time the shift key or bar is depressed to effect a shifting of the slide valves through a spring-controlled linkage mounted upon the valve plate, as hereinafter more particularly set forth and described, reference being had to Letters Patent to Lindeberg N0. 2.1801584. granted November 21, 1939, and Morrison No. 2,208,334, granted July 16, 1940.

The full nature of the invention will be understood from the accompanying drawings and the following description and claims:

2 shifter head 34 formed with adjacent arcuate camming surfaces 35, 35a arranged in camming relation with the pins 29, 29a, respectively.

The free end of the arm 28 has a pin and slot connection at 36 with a reciprocator 31 fulcrumed to the box at 38. Said reciprocator is provided with a pair of upstanding pins 39, 39a slidably extending through transverse slots provided adjacent the ends of the slides I4, I5, respectively. The pin 39a intermediate the fulcrum 38 and pin and slot connection 33 is connected by a tension spring 40 with a fixed pin 4| on the bass box.

Fig. 1 is a central vertical section through the valve plate of an accordion bass box.

Fig. 2 is a perspective view of the bass box and bass shift mechanism.

Fig. 3 is the same as Fig. 2. showing the valves shifted to the opposite position.

Fig. 4 is a modified form of the shift mechanism shown in Fig. 2.

In the drawings there is shown a section of an accordion bass box 10 which is apertured to receive thereover a valve plate II. Said valve plate is apertured to register with apertures of the bass box and the reed blocks indicated at I2, and recessed at I3 to slidably support the slide valves I4, I5.

Fulcrumed upon the valve plate II at I6 there is a pair of spaced bell crank levers I1. One end of each of said bell crank levers pivotally carries the lugs iii of a. shift bar l9 operating through an elongated opening in the face of the easing 2I.

The opposite end of each of said bell crank levers is pivotally connected to an equalizer bar 22, the rear end of said bar having a tongue 23 connected to a pin 24 by a tension spring 25, said pin 24 being mounted upon the bass box Ill. The free end of said eoualizer bar 22 terminates short of an oscillator 26 fulcrumed to the box at 21 and provided with an elongated arm 28. Said oscillator is provided with a pair of upstanding pins 29, 29a. Fulcrumed at 30 upon the adjacent end of the equalizer bar 22 there is a shifter finger 3|. To one end of said shifter finger there is secured a fiat spring 32 extending over and along the equalizer bar with its remote end slidably embraced by the spaced lugs 33. The opposite end of the shifter finger is flared to provide a.

In operation, upon depressing the shift bar I9, the equalizer bar 22 will be moved longitudinally toward the oscillator against tension of the spring 25. Cam face 35 of the shifter finger 3| being in engagement with the pin 29 of the oscillator, will swing the oscillator about its fulcrum to thereby cause its arm 28 to correspondingly swing the reciprocator 31 about its fulcrum. This action will throw the spring 40 over center and reverse the position of the valves, all to the position shown in Fig. 3.

In this position, as in Fig. 3, the same action of depressing the shift bar will cause the cam face 3% of the shifter finger engaging the pin 21a to swing the oscillator back to the position shown in Fig. 2, such as to again shift the valves. In each shifting operation. the flat spring 32 permits the shifter finger 3I to swivel about its fulcrum 33 in its pushing action upon one or the other pins 23, 29a. But as soon as the shifting pressure is released, said spring acts to return the shifter finger to its neutral position ready for the next shifting action.

Whereas the shift mechanism has herein been shown and described as applied to the slide valves on the bass box, it is similar and in precisely the same manner applicable to the shifting of the valves on the treble box. However, the shift mechanism when applied to the treble box, is operated in the usual manner by a shift key connected with the bell crank lever I1 in place of the elongated shift bar herein shown.

In the modified form shown in Fig. 4, the valves I4, I5 are shifted by a fulcrumed lever I31 in the form of a T-crank. Said lever is biased in overcenter position by the spring I40, having one end connected to the fixed pin MI and the other end connected to the pin I39a which with the pin I39 comprises the pin and slot actuating engagement between the lever and the shift valves. The elongated arm I29 of the oscillator I26 is connected to the arm of the fulcrumed lever I31 by th link I33. The shift finger I3I, operating in the mancrumed intermediate its ends adjacent the-ends-of' said valves, a pin and slot connection between said lever and valves, an oscillator pivotedttosai'd accordion having an elongated arm, a pin and slot connection between said arm and lever whereby upon oscillation of said oscillator saidlever will be swung from one position to another-;f-or. the shifting of said valves, a depressible actuating member, and means operatively connecting said actuating member withsaid oscillatorforswinging it from one position-to the other upon-each. depressing movement of saidmember.

2.. In an accordion having ,apair ofsli'de valves, ashift mechanism therefor comprising ,ajlever. fulcrumed intermediate its ends uponsaid accordion-adjacent the ends of saidvalves, meansfor operatively connectingthe ends of said'va1ves to said lever on each side of said fulcrumed lever respectively, an oscillator pivotally mounted upon said accordion having an elongated arm operatively connected with one end-of said lever for swinging said lever and valves fromone position toe another; over-center biasing means-for said lever for; yieldingly retaining it in one or ,theother of itspositions; and a depressible member manually operable to swing said oscillator from one position to another upon each depressing movement thereof.

3. In an accordionhaving a pair ofslide-valves, a shift mechanism-therefor comprisingalever fulcrumed intermediate its ends upon said accordion adjacent the ends of said valves, means-for operatively connecting theends of said valves'to, said lever on eachside ofsaid fulcrumedlever respec tively, an oscillator pivotallymounted upon said accordion having an elongated arm operatively connected with one endof ai-d lever for swinging saidlever andrvalvesfromone position to another, over-center biasing means for said leverfor yieldinglyretaining itin, one or the other of its positions, a shifter bar, a shifter finger pivotally mounted on said bar, spaced projectionsron said oscillator alternately engageableby said finger to swingsaidoscillator from, one position toanother when. moved in one direction, and a depressible member manually operable tomovesaid shifter bar andfinger ina direction to swing said oscillator to its opposite position on each depressed movementthereof.

4. Inan accordion'having a pair of slidevalves, a-shiftmechanism thereforcomprising a lever fulcrumed intermediate it -ends adjacent the-ends of said valves, anoperative connection between said valves, a lever arrangedon each side of said-fulcrum point respectively, an oscillator pivoted to said accordion having an elongated arm, a connection between said arm and lever for swinging said lever about its fulcrum point upon the oscillatory movement of said oscillator, a pair of Spaced pins on ,said oscillator, a longitudinal shiftable bar biased in retractable position, a depressble a tuating ember perat ve y connected with said bar for moving it from retracted position,

and a shift finger pivoted to said bar for alternate actuating engagement with said pins respectively, whereby upon each depression of said member said oscillator will be swung from one position to the other,

5. In an accordion having a pair of slide valves, 9, shift mechanism therefor comprising a lever fulcrumed'intermediate its ends adjacent the ends of said valves, an operative connection between said valves and lever arranged on each side of said fulcrum point respectively, an oscillator pivoted to said accordion having an elongated arm, a oonnectionbetween said arm and lever for swing- ;ing -s.aid lever about its fulcrum point upon the oscillatory-movement of said oscillator, a pair of spaced pins on said oscillator, a longitudinally shiftable bar biased in retracted position, a depressible actuating member operatively connected with said bar for moving it from retracted positiomashift finger pivoted to said bar for alternate actuating engagement with said pin respectively, andaspring interconnecting said shift bar with said shift finger for biasing said finger in alignment therewith while permitting it to swing against spring tension upon actuation of said oscillator, whereby upon each depression of said member said oscillator will be swung from one position to the'other.

6. In anaccordion having a pair-of slide valves, a shift mechanism therefor comprising a lever fulcrumed-intermediate its ends adjacent-the ends of said valves, an operative connection between said valves and lever arranged on eachside of said fulcrum point respectively, an oscillator pivoted to said accordion having an elongated arm, a connection between said arm and lever for swinging said lever about its fulcrum point upon the oscillatory movement of said oscillator, a pair of spaced pins' on said oscillator, a longitudinally shiftable bar biased in retracted position, a depressible actuating member operatively connected with said bar for moving it from retracted position, a shift finger pivotedto said bar for alternate actuating engagement with said pins respectively, and a flat tension spring having its opposite ends connected to said shift finger and bar respectively for biasing them in alignment while permitting said finger to yieldingly follow the movement of. the oscillator upon being actuated thereby, whereby upon each depression of said member said oscillator will be swung from one position to the other.

7; In an accordion having a pair of slide valves, a shift mechanism therefor comprising a lever fulcrumed intermediate its ends adjacent the ends of said valves, an operative connection between said valves and lever arranged on each side of said fulcrum point respectively, an oscillator pivoted to said accordion having an elongated arm, a connection between said arm and lever for swinging said lever about its fulcrum point upon the oscillatory movement of said oscillator, a pair of spaced pins on said oscillator, a longitudinally shiftable bar biased in retracted position, a depressibleactuating member operatively connected with said bar for moving it from retracted position, a shift finger pivoted to said bar for alternate actuating engagement with said pins respectively, a pair of camming surfaces formed on the end. of said shift finger for slidable engagement with said pins respectively, and a spring for biasing said shift finger and bar in alignment while permitting said finger to swing with the corresponding movement of the oscillator and shift to REFERENCES CITED The following references are of record in the file of this patent:

Number UNITED STATES PATENTS Name Date Lindeberg Nov. 21, 1939 

